Persistence of spermatozoa and prostatic acid phosphatase in specimens from deceased individuals during varied postmortem intervals

The survival of spermatozoa and the persistence of prostatic acid phosphata se has been an area of interest for investigators of sexual assault. Howeve r, not much documentation exists concerning the examination of a deceased i ndividual with regard to the postmortem interval and presence of such evide nce. The authors reviewed cases referred to the medical examiner's office d uring a 10-year period. During this time, 199 cases were both autopsied and examined for sexual assault. In particular, these examinations included pr ocurement of swabs for Papanicolaou staining of smears and for quantitation of prostatic acid phosphatase. Most of the victims were female, although a few were male. In the majority of cases, the swabs for smears and prostati c acid phosphatase were taken from oral, vaginal, and anorectal areas in fe males and oral and anorectal areas in males. The smears all were stained wi th the routine Papanicolaou stain, and intact spermatozoa and spermatozoan heads were sought. The prostatic acid phosphatase was analyzed by the micro particle enzyme immunoassay method and reported as ng/ml. A level of greate r than 100 ng/ml was considered positive. The cases were analyzed with resp ect to postmortem interval; presence or absence of intact spermatozoa or sp ermatozoan heads; presence of an elevated prostatic acid phosphatase; body location of the specimen; the time of year; location of the victim; and phy sical injury (anogenital) of sexual assault. The authors hope that by exami ning the laboratory evidence of sexual assault, a correlation can be drawn between the presence or absence of such evidence and the aforementioned var iables.